code: def predict(self, obs):
      obs = np.expand_dims(obs, axis=0)
      act = self.fluid_executor.run(
          self.pred_program,
          feed={"obs": obs},
          fetch_list=[self.pred_act],
      )[0]
      act = np.squeeze(act)
      return act
  
file_path: PARL/examples/tutorials/lesson5/ddpg/agent.py
imports: import numpy
  import parl
  from parl import layers
  from paddle import fluid
label_desc: Use image node_id 3 for calling the Agent obj's underlying member method code with example usage: obj.predict(obs) and returns: act